Network Fundamentals

An open-access knowledge base for network engineering protocols, standards, and architecture.

Core Protocols
Layer 1-2

Ethernet & Switching

802.3 standards, MAC addressing, VLANs, Spanning Tree Protocol (STP), and frame structures.

Layer 3

IP Addressing

IPv4/IPv6 packet headers, CIDR subnetting, fragmentation, and MTU mechanics.

Layer 3

Routing Protocols

OSPF, EIGRP, and BGP. Path selection algorithms, metric calculations, and convergence.

Layer 4

Transport Layer

TCP flow control, windowing, UDP characteristics, and the 3-way handshake.

Advanced Topics
Architecture

Data Center & Cloud

Leaf-Spine topologies, VXLAN/EVPN overlays, and SDN control planes.

Security

Network Security

ACLs, IPsec/SSL VPNs, Zone-based Firewalls, and 802.1X identity management.

DevOps

Network Automation

Infrastructure as Code, Python (Netmiko), Ansible, and REST API integration.

Traffic Engineering

Quality of Service

Classification, marking (DSCP), queuing mechanisms (LLQ), and shaping/policing.

Tools & Resources
Assessment

Exam Simulator

Randomized practice questions for CCNA/CCNP certification preparation.

Professional

Career Path

Role definitions, salary data, and certification roadmaps for engineers.